Know what you’re dealing with by site when you use these reference charts for soil, sand, and rock.
Start with the sand grain size cards so that you can know what type of sand you’re dealing with, from silt to coarse. We also carry rock color charts, arranged by hue, value, and gamma, as well as a soil color chart so that you can note the exact color. And if you can have just one geologist tool to keep in your glovebox, make sure it’s the geotechnical gauge. The gauge covers grain size, colors, soil classification systems, a ruler, and even more ways to identify soil and rock in the field.